Self-watering plant tray



FIG. 1 is a reduced perspective view of a self-watering plant tray showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is an end elevational view thereof;

FIG. 4 is an enlarged bottom perspective view thereof. 

The ornamental design for a self-watering plant tray, substantially as shown and described. 